Vacuum operated synchronizing device for compounded internal-combustion engines



Sept" 5, 1950 D. ELLIS VACUUM OPERATED SYNCHRONIZING DEVICE FORCOMPOUNDED INTERNAL-COMBUSTION ENGINES 2 Sheets-Sheet 1 Filed Dec. 10,1947 Qm NW Dee Ell/s INVENTOR.

I WWWFW Sept. 5, 1950 2,521,053

D. ELLIS VACUUM OPERATED SYNCHRONIZING DEVICE FOR COMPOUNDEDINTERNAL-COMBUSTION ENGINES 2 Sheets-Sheet 2 Filed Dec. 10, 1947 DeeEll/s IN V EN TOR.

A Name Patented Sept. 5, 1950 UNITED STATES PATENT OFFICE VACUUMOPERATED SYNCHRONIZING DE- VICE FOR COMPOUNDED INTERNAL-COM- BUSTIONENGINES I 4 Claims.

My invention relates to improvements in synchronizing devices forinternal combustion engines compounded on a single load.

The primary object of the invention is to provide an eflicient,practical device for accurately controlling the speed of an internalcombustion engine compounded with a pilot internal combustion engine,and through operation of the pilot engine, so that both engines willoperate at the same speed relatively Without either momentarily laggingbehind the other.

Another object is to provide a device of the character and for thepurpose above set forth which is simple in construction, avoids the useof objectionable diaphragms and leaky packing nuts, is easily toinstall, and economical to service and manufacture.

Other and subordinate objects, within the purview of my invention,together with the precise nature of my improvements will be readilyunderstood when the succeeding description and claims are read withreference to the drawings accompanying and forming part of thisspecification.

In said drawings:

Figure 1 is a view in plan of my improved synchronizing device in apreferred embodiment thereof;

Figure 2 is a view in side elevation;

Figure 3 is a view in vertical longitudinal section taken on the line 33of Figure 1 and with the yoke and vacuum lines eliminated for clearnessof illustration;

' Figure 4 is a view in end elevation;

Figure 5 is a view in transverse section taken on the line 5-5 of Figure3.

Referring to the drawings by numerals, ac-- cording to my invention, asillustrated, a synchronizing device is provided, the basic elements ofwhich are a cylinder I, of any suitable size,

suitable leakproof cylinder heads closing the same, for instance endplugs 2 threaded into opposite ends of the cylinder, and an elongatedpiston 3 in said cylinder I endwise movable in opposite directions underthe influence of vacuum created in the cylinder l at opposite endsthereof, in a manner to be described.

A U-shaped bracket 4 of bar-like form is provided for supporting thecylinder I and mounting the same in a horizontal position on anysuitable fixed base, not shown, the ends 5 of said bracket straddlingthe ends of said cylindel- I and being connected thereto by set bolts 6threaded through the ends 5 and bosses l on said ends, said set bolts 6being threaded through the end plugs 2 into the cylinder I in the axisof said cylinder for setting to variably limit the stroke of the piston3 in opposite directions, as occasion may require.

To reduce friction, the piston 3 is formed with circumferential endflanges 8 for engaging the cylinder wall, and with a pair of similar,relatively narrower, intermediate flanges 9 equidistantly spaced uponopposite sides of the transverse center of said piston, and also forengaging the cylinder wall. A pair of piston rings II) are provided ineach end flange 8, for the usual purpose.

The flanges 9 adapt the piston 3 to form, with the cylinder wall, an oildistributing well II around said cylinder I. A radial oil feed port I2in the piston 3 extends in the transverse center of said piston fromsaid well I I to a longitudinal oil feed duct I3 in said piston at oneside thereof and which terminates in branch ends I4 opening intocircumferential oil discharge grooves I5 in the flanges 8 intermediatethe pairs of piston rings I0. A set screw H5 in the bottom of the feedport I2 serves a purpose to be explained.

An oil cup IT with a discharge line I1 tapped into the cylinder I todischarge into the oil well I I supplies oil for lubricating the piston3 and wall of the cylinder I.

Straddling the cylinder I is a throttle valve operating yoke I8 adaptedto be moved endwise by such movement of the piston 3 and to which saidpiston is operatlvely connected as follows. A cross bolt I9 extendsdiametrically through a suitable diametrical bore 20 in the transversecenter of the piston 3, said bolt I9 having its ends extending out ofand slidably fitted in a pair of longitudinal slots 2| in opposite sidesof the cylinder I.

The before mentioned set screw I8 clamps said bolt IQ in the bore 29.The ends of the cross bolt l9 extend through eyes 22 on one end of theyoke I8. Nuts 23 on said ends of the cross bolt I8 secure said eyes 22on said cross bolt is for pivotal compensating movement of said yoke I8vertically for a purpose presently seen. An end coupling 24, ofuniversal joint form, provides for coupling the yoke I8 at the other endthereof to the throttle lever, not shown, of a carburetor of an internalcombustion engine.

Extending through the end plug 2 in one end of the cylinder I,hereinafter termed the primary end, and opening into said end is avacuum line 25 adapted to be connected, in any suitable manner, to theintake manifold of a pilot internal combustion engine, not shown.Similarly extending through the end plug 2 in the other end of saidcylinder I, hereinafter termed the secondary end, and opening into saidend is a vacuum line 26 adapted to be suitably connected to the intakemanifold of a second internal combustion engine, not shown, arranged forcompounding with the pilot engine on a single load.

A pair of vacuum breaking bleed lines 21, 28 extend into said plugs 2and open into the primary and secondary ends of said cylinder I, saidlines being designed to be opened by a suitable bleed valve, not shown,in each line.

Referring now to the use and operation of the invention, as so fardescribed: with the vacuum lines 25, 26 connected to the intakemanifolds of the pilot internal combustion engine and. the secondengine, respectively, the bleed lines 21,. 28 closed, and the coupling24 attached to the throttle valve lever of the carburetor of the secandengine, if bothengines be dead, the piston 3 is held in a restpositionin the cylinder l, for instance that shown in Figure 3, by saidlever through the usual spring tension on the lever.

Now, with both engines running, the vacuum created in the intakemanifolds will create suction in both ends of the cylinder and as longas thesuction is equal in said ends of the cylinder, as will be the caseif both engines are operating at the same speed, the piston 3 will notbemoved from the position in which it was adjusted by opening movementof the throttle valve lever of the second engine. However, if'the pilotengine is slowed down, relative to the second engine, as, for instance,by closing of the throttle valve of the pilot engine, the vacuum in theintake manifold for the pilot engine will increase over that in theintake manifold for the second engine. This will result in greatersuction in the primary end ofthe cylinder I, than in the secondary endthereof, and in causing the piston 3 to be moved toward said primary endso that the yoke l8 will be shoved in one direction to close thethrottle valve for the second engine and thereby slow down said secondengine in correspondence with the pilot engine. On the other hand, ifthe pilot engine is accelerated, the vacuum in the intakemanifoldtherefor will drop and the greater vacuum in the intake manifoldfor thesecond engine will cause a greater suction in the secondary end of thecylinder 1 resulting in movement of piston 3 toward said secondary endand pulling of said yoke 18 in the opposite direction to cause openingof the throttle valve for the second engine whereby the second enginewill be accelerated in correspondence with the pilot engine.

By'opening either bleed line 21, 28 the device may be disabled at eitherend of the cylinder I" for adjusting or other purposes.

As is well known, the butterfly throttle valves ofint'ernal combustionengines, when closed, have a tendency to flutter under the action ofair'being drawn into the carburetor. Also engines with butterflythrottle valves and operating with high manifold vacuum and under lightload have a tendency to flutter. Ihis fluttering tends to cause surgingin engine. operation.

To overcome suchsurging, the following means are provided. A pair ofupright rocker bars 29 arranged upon opposite sides of the cylinder Iare pivoted intermediate the ends thereof, as at 2 9", on upstandingears 36 of a yoke 3| suitably secured on the top-of the cylinder l inthe transverse center thereof toextend' across the same.

By means of longitudinal slots 32 in the lower ends of said bars 29, andthrough which the cross bolt l9 slidably extends, said arms areconnected to the piston 3 to be rocked thereby in opposite directions.Annular counterweights 33 are provided between the upper ends of saidbars 29 to rock on a bolt 34 extending through said counterweights, andthrough said upper ends of said bars 29 with nut 35 thereon securingsaidbolt in place. As the piston 3 moves in either direction from restposition, it is counterweighted against movement in the oppositedirection by the'described' means. This prevents surging action of thepiston as a result of momentary variations in vacuum in the intakemanifolds and surging in either engine from similarly affecting theother engine;

The foregoing will, it is believed, suffice to impart a clearunderstanding of my invention, without further explanation.

Manifestly, the invention, as described, issusceptible of modification,without departing'from the inventive" concept, andv right ishereinres'erved to such modifications as fall within" the scope of. theappended claims.

Having described the invention, what is claimed as new is:

l. A speed synchronizing device for attachment to the intake manifoldsof a pair'ot'internal combustion engines and to the throttle valve ofone engine, said device comprising a cylinder with closed ends, a pistonworking inthe cylinder, a pair of vacuum: lines extending from-oppositeends ofv the cylinder and-adapted to be com nected to said manifoldswhereby variations in the vacuum in either manifold relative tothat inthe other manifold will create suction in one or the other end of thecylinder causing movement of said piston, means operative such movementof the piston adapted to be connected to said throttle valve to causeoperation of: said valve, and swingabl'e' counterweight mechanism forthe piston swingable thereby into effective position to obviatefluttering operation of said piston.

2. A speed synchronizingdevice for: attachment to the intake manifoldsof a pairof internal combustion engines and to the throttle valve-of oneengine, said device comprising a cylinder with closed ends, a pistonworking inthecylinder, a pair of vacuum lines extending from oppositeends of the cylinder and adaptedto beconnected to said manifolds wherebyvariations in the vacuum in either manifold relative to that in theother manifold will create suction in one or the other end of thecylinder causingmovement of said piston, means operative by suchmovement' of the piston adapted to be connected to said throttle valveto cause operation of said valve, and swingable counterweight mechanismfor the piston swingable thereby into effective position to obviatefluttering operation of said piston comprising opposite bars pivotallymounted on said cylinder in connection with said piston, a crossconnection between said bars, and weights s'wingably mounted on saidcross connection.

3. In a speed synchronizing device of the class described, a cylinder, apiston in said cylinder, vacuum lines connected to said cylinder formoving the piston in opposite directions alternately under the influenceofvacuum in said lines, and swingable counterweight mechanism for saidpiston swingable thereby into eifective position to obviate flutteringof said piston.

4. In a speed synchronizing deviceof the-class 5 described, a cylinder,a piston in said cylinder, vacuum lines connected to said cylinder formoving the piston in opposite directions alternately under the influenceof vacuum, and swingable counterweight mechanism for said piston swing-5 able thereby into effective position to obviate fluttering of saidpiston comprising opposite bars pivotally mounted on said cylinder inconnection with said piston, a cross connection between said bars, andweights swingably mounted on said 10 cross connection.

DEE ELLIS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,233,003 Wall July 10, 19171,328,437 Lang Jan. 20, 1920 1,668,304 Caldwell May 1, 1928 1,784,671Jehle Dec. 9, 1930 2,381,429 Bell et a1. Aug. 7, 1945

